Finding Arrowheads

arrow_head_spike_tailThe arrowhead spiketail (Cordulegaster obliqua) is a large, impressive dragonfly found in the eastern United States and up into southeastern Canada. It can be seen in our area from June to July. Measuring in at just over three inches long, it is the largest of our four local spiketail species. Typical of dragonflies in the family Cordulegastridae, the arrowhead spiketail has a dark body with bright yellow markings that help you to distinguish one species from another. Two yellow diagonal stripes down the sides of the thorax coupled with yellow arrowheads running along the top of the abdomen identify this species. Juveniles have grayish eyes, but the adults have lovely bright green eyes here in the North and bright blue eyes in the southern states.

Spiketail dragonflies don’t hang out in your typical dragonfly haunts, so you won’t see them patrolling along the sunny surfaces of ponds or lakes. Look for them in wooded habitats along seeps and muddy-bottomed streamlets. The arrowhead spiketail is one of a few species that will patrol low over a small stream, following the course of the water. If you notice a large dragonfly buzz past your knees to disappear downstream, give it a moment and it will surely be back. It is likely to be a male spiketail that has claimed this section of trickling water as its territory. If the dragonfly holds its body vertically above the shallow water while dipping the tip of its abdomen into the muck below, it is a female laying her eggs. She will remind you of a sewing machine needle as she repeatedly plunges her ovipositor into the mud.

The arrowhead spiketail can also be encountered feeding along forest edges. While many species of dragonflies will swarm together when feeding, the arrowhead spiketail has a more solitary nature. It feeds alone and when disturbed it is known to fly straight up over the trees and disappear. But it will also perch on low vegetation and twigs, giving you an opportunity to see its arrowheads for yourself.

Submitted by Cindi Kobak
Photo by Cindi Kobak